title: Psychogenic paroxysmal movement disorders--clinical features and diagnostic clues.
abstract: BACKGROUND
  The diagnosis of psychogenic paroxysmal movement disorders (PPMD) can be challenging, in particular their distinction from the primary paroxysmal dyskinesias (PxD) remains difficult.
  
  
  METHODS
  Here we present a large series of 26 PPMD cases, describe their characteristics, contrast them with primary PxD and focus on their distinguishing diagnostic features.
  
  
  RESULTS
  Mean age at onset was 38.6 years, i.e. much later than primary PxD. Women were predominantly affected (73%). Most subjects (88.4%) had long attacks, and unlike primary PxD there was a very high within-subject variability for attack phenomenology, duration and frequency. Dystonia was the most common single movement disorder presentation, but 69.2% of the patients had mixed or complex PxD. In 50% of PPMD cases attack triggers could be identified but these were unusual for primary PxD. 42.3% of patients employed unusual strategies to alleviate or stop the attacks. Response to typical medication used for primary PxD was poor. Precipitation of the disorder due to physical or emotional life events and stressors were documented in 57.6% and 65.3% of the cases respectively. Additional interictal psychogenic signs were documented in 34.6% and further medically unexplained somatic symptoms were present in 50% of the cases. 19.2% of patients had a comorbid organic movement disorder and 26.9% had pre-existing psychiatric comorbidities.
  
  
  CONCLUSIONS
  Although the phenotypic presentation of PPMD can be highly diverse, certain clinical characteristics help in distinguishing this condition from the primary forms of PxD. Recognition is important as multidisciplinary treatment approaches led to significant improvement in most cases.
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Department of Neurology, University Medical Center Hamburg-Eppendorf (UKE), Hamburg, Germany.
authors.forename: Christos
authors.initials: C
authors.lastname: Ganos
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
authors.forename: Maria
authors.initials: M
authors.lastname: Aguirregomozcorta
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
authors.forename: Amit
authors.initials: A
authors.lastname: Batla
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Second Department of Neurology, Attiko Hospital, University of Athens, Greece; Neurology Clinic, Philipps University, Marburg, Germany.
authors.forename: Maria
authors.initials: M
authors.lastname: Stamelou
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK; Department of Neurology, Medical University of Graz, Graz, Austria.
authors.forename: Petra
authors.initials: P
authors.lastname: Schwingenschuh
authors.affiliation: Department of Paediatric and Adult Movement Disorders and Neuropsychiatry, Institute of Neurogenetics, University of Lübeck, Lübeck, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Münchau
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK.
authors.forename: Mark J
authors.initials: MJ
authors.lastname: Edwards
authors.affiliation: Sobell Department of Motor Neuroscience and Movement Disorders, UCL Institute of Neurology, University College London, Queen Square, London WC1N 3BG, UK. Electronic address: K.bhatia@ion.ucl.ac.uk.
authors.forename: Kailash P
authors.initials: KP
authors.lastname: Bhatia
mesh_terms: D000293:Adolescent; D000328:Adult; D017668:Age of Onset; D000368:Aged; D000369:Aged, 80 and over; D002819:Chorea / Q000175:diagnosis*; D004569:Electroencephalography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D013001:Somatoform Disorders / Q000175:diagnosis*; D014741:Video Recording; D055815:Young Adult
keywords: PED; PKD; PNKD; Paroxysmal dyskinesias; Psychogenic movement disorders